Files
NotAlwaysTrue 59bc21973a OBT/1.2.0(Spring Update)
Sync with Upstream
2026-04-25 13:25:41 +08:00

400 lines
15 KiB
C#

using Microsoft.Xna.Framework;
using Sigil;
using Sigil.NonGeneric;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq.Expressions;
using System.Reflection;
namespace Barotrauma.LuaCs;
internal static class SigilExtensions
{
/// <summary>
/// Puts a type on the stack, as a <see cref="Type" /> object instead of a
/// runtime type token.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="type">The type to put on the stack.</param>
public static void LoadType(this Emit il, Type type)
{
if (type == null) throw new ArgumentNullException(nameof(type));
il.LoadConstant(type); // ldtoken
// This converts the type token into a Type object
il.Call(typeof(Type).GetMethod(
name: nameof(Type.GetTypeFromHandle),
bindingAttr: BindingFlags.Public | BindingFlags.Static,
binder: null,
types: new Type[] { typeof(RuntimeTypeHandle) },
modifiers: null));
}
/// <summary>
/// Converts the value on the stack to <see cref="object" />.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="type">The type of the value on the stack.</param>
public static void ToObject(this Emit il, Type type)
{
if (type == null) throw new ArgumentNullException(nameof(type));
il.DerefIfByRef(ref type);
if (type.IsValueType)
{
il.Box(type);
}
else if (type != typeof(object))
{
il.CastClass<object>();
}
}
/// <summary>
/// Deferences the value on stack if the provided type is ByRef.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="type">The type to check if ByRef.</param>
public static void DerefIfByRef(this Emit il, Type type) => il.DerefIfByRef(ref type);
/// <summary>
/// Deferences the value on stack if the provided type is ByRef.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="type">The type to check if ByRef.</param>
public static void DerefIfByRef(this Emit il, ref Type type)
{
if (type == null) throw new ArgumentNullException(nameof(type));
if (type.IsByRef)
{
type = type.GetElementType();
if (type.IsValueType)
{
il.LoadObject(type);
}
else
{
il.LoadIndirect(type);
}
}
}
// Copied from https://github.com/evilfactory/moonsharp/blob/5264656c6442e783f3c75082cce69a93d66d4cc0/src/MoonSharp.Interpreter/Interop/Converters/ScriptToClrConversions.cs#L79-L99
private static MethodInfo GetImplicitOperatorMethod(Type baseType, Type targetType)
{
try
{
return Expression.Convert(Expression.Parameter(baseType, null), targetType).Method;
}
catch
{
if (baseType.BaseType != null)
{
return GetImplicitOperatorMethod(baseType.BaseType, targetType);
}
if (targetType.BaseType != null)
{
return GetImplicitOperatorMethod(baseType, targetType.BaseType);
}
return null;
}
}
/// <summary>
/// Loads a local variable and casts it to the target type.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="value">The value to cast. Must be of type <see cref="object" />.</param>
/// <param name="targetType">The type to cast into.</param>
public static void LoadLocalAndCast(this Emit il, Local value, Type targetType)
{
if (value == null) throw new ArgumentNullException(nameof(value));
if (targetType == null) throw new ArgumentNullException(nameof(targetType));
if (value.LocalType != typeof(object))
{
throw new ArgumentException($"Expected local type {typeof(object)}; got {value.LocalType}.", nameof(value));
}
var guid = Guid.NewGuid().ToString("N");
if (targetType.IsByRef)
{
targetType = targetType.GetElementType();
}
// IL: var baseType = value.GetType();
var baseType = il.DeclareLocal(typeof(Type), $"cast_baseType_{guid}");
il.LoadLocal(value);
il.Call(typeof(object).GetMethod("GetType"));
il.StoreLocal(baseType);
// IL: var implicitOperatorMethod = SigilExtensions.GetImplicitOperatorMethod(baseType, <targetType>);
var implicitOperatorMethod = il.DeclareLocal(typeof(MethodInfo), $"cast_implicitOperatorMethod_{guid}");
il.LoadLocal(baseType);
il.LoadType(targetType);
il.Call(typeof(SigilExtensions).GetMethod(nameof(GetImplicitOperatorMethod), BindingFlags.NonPublic | BindingFlags.Static));
il.StoreLocal(implicitOperatorMethod);
// IL: <TargetType> castValue;
var castValue = il.DeclareLocal(targetType, $"cast_castValue_{guid}");
// IL: if (implicitConversionMethod != null)
il.LoadLocal(implicitOperatorMethod);
il.Branch((il) =>
{
// IL: var methodInvokeParams = new object[1];
var methodInvokeParams = il.DeclareLocal(typeof(object[]), $"cast_methodInvokeParams_{guid}");
il.LoadConstant(1);
il.NewArray(typeof(object));
il.StoreLocal(methodInvokeParams);
// IL: methodInvokeParams[0] = value;
il.LoadLocal(methodInvokeParams);
il.LoadConstant(0);
il.LoadLocal(value);
il.StoreElement<object>();
// IL: castValue = (<TargetType>)implicitConversionMethod.Invoke(null, methodInvokeParams);
il.LoadLocal(implicitOperatorMethod);
il.LoadNull(); // first parameter is null because implicit cast operators are static
il.LoadLocal(methodInvokeParams);
il.Call(typeof(MethodInfo).GetMethod("Invoke", new[] { typeof(object), typeof(object[]) }));
if (targetType.IsValueType)
{
il.UnboxAny(targetType);
}
else
{
il.CastClass(targetType);
}
il.StoreLocal(castValue);
},
(il) =>
{
// IL: castValue = (<TargetType>)value;
il.LoadLocal(value);
if (targetType.IsValueType)
{
il.UnboxAny(targetType);
}
else
{
il.CastClass(targetType);
}
il.StoreLocal(castValue);
});
il.LoadLocal(castValue);
}
/// <summary>
/// Emits a call to <see cref="string.Format(string, object[])"/>.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="format">The string format.</param>
/// <param name="args">The local variables passed to string.Format.</param>
public static void FormatString(this Emit il, string format, params Local[] args)
{
if (format == null) throw new ArgumentNullException(nameof(format));
if (args == null) throw new ArgumentNullException(nameof(args));
var guid = Guid.NewGuid().ToString("N");
var listType = typeof(List<>).MakeGenericType(typeof(object));
var list = il.DeclareLocal(listType, $"formatString_list_{guid}");
il.NewObject(listType);
il.StoreLocal(list);
foreach (var arg in args)
{
il.LoadLocal(list);
il.LoadLocal(arg);
il.ToObject(arg.LocalType);
il.CallVirtual(listType.GetMethod("Add", new[] { typeof(object) }));
}
var arr = il.DeclareLocal<object[]>($"formatString_arr_{guid}");
il.LoadLocal(list);
il.CallVirtual(listType.GetMethod("ToArray", new Type[0]));
il.StoreLocal(arr);
il.LoadConstant(format);
il.LoadLocal(arr);
il.Call(typeof(string).GetMethod("Format", new[] { typeof(string), typeof(object[]) }));
}
/// <summary>
/// Emits a call to <see cref="DebugConsole.NewMessage(string, Color?, bool)" />.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="message">The message to print.</param>
public static void NewMessage(this Emit il, string message)
{
var newMessage = typeof(DebugConsole).GetMethod(
name: nameof(DebugConsole.NewMessage),
bindingAttr: BindingFlags.Public | BindingFlags.Static,
binder: null,
types: new Type[] { typeof(string), typeof(Color?), typeof(bool) },
modifiers: null);
il.LoadConstant(message);
il.Call(typeof(Color).GetProperty(nameof(Color.LightBlue), BindingFlags.Public | BindingFlags.Static).GetGetMethod());
il.LoadConstant(false);
il.Call(newMessage);
}
/// <summary>
/// Emits a call to <see cref="DebugConsole.NewMessage(string, Color?, bool)" />,
/// using the string on the stack.
/// </summary>
/// <param name="il">The IL emitter.</param>
public static void NewMessage(this Emit il)
{
var newMessage = typeof(DebugConsole).GetMethod(
name: nameof(DebugConsole.NewMessage),
bindingAttr: BindingFlags.Public | BindingFlags.Static,
binder: null,
types: new Type[] { typeof(string), typeof(Color?), typeof(bool) },
modifiers: null);
il.Call(typeof(Color).GetProperty(nameof(Color.LightBlue), BindingFlags.Public | BindingFlags.Static).GetGetMethod());
il.LoadConstant(false);
il.Call(newMessage);
}
/// <summary>
/// Emits a <c>foreach</c> loop that iterates over an <see cref="IEnumerable{T}"/> local variable.
/// </summary>
/// <typeparam name="T">The type of elements in the enumerable.</typeparam>
/// <param name="il">The IL emitter.</param>
/// <param name="enumerable">The enumerable.</param>
/// <param name="action">The body of code to run on each iteration.</param>
public static void ForEachEnumerable<T>(this Emit il, Local enumerable, Action<Emit, Local, Sigil.Label> action)
{
if (enumerable == null) throw new ArgumentNullException(nameof(enumerable));
if (action == null) throw new ArgumentNullException(nameof(action));
if (!typeof(IEnumerable<T>).IsAssignableFrom(enumerable.LocalType))
{
throw new ArgumentException($"Expected local type {typeof(IEnumerator<T>)}; got {enumerable.LocalType}.", nameof(enumerable));
}
var guid = Guid.NewGuid().ToString("N");
var enumerator = il.DeclareLocal<IEnumerator<T>>($"forEachEnumerable_enumerator_{guid}");
il.LoadLocal(enumerable);
il.CallVirtual(typeof(IEnumerable<T>).GetMethod("GetEnumerator"));
il.StoreLocal(enumerator);
ForEachEnumerator<T>(il, enumerator, action);
}
/// <summary>
/// Emits a <c>foreach</c> loop that iterates over an <see cref="IEnumerator{T}"/> local variable.
/// </summary>
/// <typeparam name="T">The type of elements in the enumerable.</typeparam>
/// <param name="il">The IL emitter.</param>
/// <param name="enumerator">The enumerator.</param>
/// <param name="action">The body of code to run on each iteration.</param>
public static void ForEachEnumerator<T>(this Emit il, Local enumerator, Action<Emit, Local, Sigil.Label> action)
{
if (enumerator == null) throw new ArgumentNullException(nameof(enumerator));
if (action == null) throw new ArgumentNullException(nameof(action));
if (!typeof(IEnumerator<T>).IsAssignableFrom(enumerator.LocalType))
{
throw new ArgumentException($"Expected local type {typeof(IEnumerator<T>)}; got {enumerator.LocalType}.", nameof(enumerator));
}
var guid = Guid.NewGuid().ToString("N");
var labelLoopStart = il.DefineLabel($"forEach_loopStart_{guid}");
var labelMoveNext = il.DefineLabel($"forEach_moveNext_{guid}");
var labelLeave = il.DefineLabel($"forEach_leave_{guid}");
il.BeginExceptionBlock(out var exceptionBlock);
il.Branch(labelMoveNext); // MoveNext() needs to be called at least once before iterating
il.MarkLabel(labelLoopStart);
// IL: var current = enumerator.Current;
var current = il.DeclareLocal<T>($"forEachEnumerator_current_{guid}");
il.LoadLocal(enumerator);
il.CallVirtual(enumerator.LocalType.GetProperty("Current").GetGetMethod());
il.StoreLocal(current);
action(il, current, labelLeave);
il.MarkLabel(labelMoveNext);
il.LoadLocal(enumerator);
il.CallVirtual(typeof(IEnumerator).GetMethod("MoveNext"));
il.BranchIfTrue(labelLoopStart); // loop if MoveNext() returns true
// IL: finally { enumerator.Dispose(); }
il.BeginFinallyBlock(exceptionBlock, out var finallyBlock);
il.LoadLocal(enumerator);
il.CallVirtual(typeof(IDisposable).GetMethod("Dispose"));
il.EndFinallyBlock(finallyBlock);
il.EndExceptionBlock(exceptionBlock);
il.MarkLabel(labelLeave);
}
/// <summary>
/// Emits a branch that only executes if the last value on the stack
/// is truthy (e.g. non-null references, 1, etc).
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="action">The body of code to run if the value is truthy.</param>
public static void If(this Emit il, Action<Emit> action)
{
if (action == null) throw new ArgumentNullException(nameof(action));
il.Branch(@if: action);
}
/// <summary>
/// Emits a branch that only executes if the last value on the stack
/// is falsy (e.g. null references, 0, etc).
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="action">The body of code to run if the value is falsy.</param>
public static void IfNot(this Emit il, Action<Emit> action)
{
if (action == null) throw new ArgumentNullException(nameof(action));
il.Branch(@else: action);
}
/// <summary>
/// Emits two branches that diverge based on a condition -- analogous
/// to an if-else statement. If either <paramref name="if"/>
/// or <paramref name="else"/> are omitted, it behaves the same as
/// <see cref="If(Emit, Action{Emit})"/>
/// and <see cref="IfNot(Emit, Action{Emit})"/>.
/// </summary>
/// <param name="il">The IL emitter.</param>
/// <param name="if">The body of code to run if the value is truthy.</param>
/// <param name="else">The body of code to run if the value is falsy.</param>
public static void Branch(this Emit il, Action<Emit> @if = null, Action<Emit> @else = null)
{
if (@if == null && @else == null) throw new ArgumentException("At least one of the two branches must be defined.");
var guid = Guid.NewGuid().ToString("N");
var labelEnd = il.DefineLabel($"branch_end_{guid}");
if (@if != null && @else != null)
{
var labelElse = il.DefineLabel($"branch_else_{guid}");
il.BranchIfFalse(labelElse);
@if(il);
il.Branch(labelEnd);
il.MarkLabel(labelElse);
@else(il);
}
else if (@if != null)
{
il.BranchIfFalse(labelEnd);
@if(il);
}
else
{
il.BranchIfTrue(labelEnd);
@else(il);
}
il.MarkLabel(labelEnd);
}
}